After it launched a portable tentlike structure that lets maintenance workers better contain dust and mold, Los Angeles-based Mintie Technologies watched sales increase from $1 million in 2002 to about $9 million in 2005.

AIR APPARENT: Workers at Mintie, which services air-conditioning systems, noticed one day that 16 patients at a La Jolla, Calif., hospital got sicker after inhaling bacteria from dust kicked up by construction work. That led the firm to invent the inflatable Environmental Containment Unit, which provides an impermeable workspace. Hospitals in 50 states now use it.

SEALING DEALS: Mintie is targeting airports, cruise ships, and the military with a new product that transforms small spaces into isolation wards. Says Jim, 47: "From Katrina to bioterrorism to a SARS outbreak, this could prevent another rude wakeup call."